The Value of Honeypots

Are honeypots the right security tool for you? Explore the world of honeypots and discover the advantages, disadvantages, and the role that honeypots play in overall security.

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This chapter is from the book

This chapter is from the book

Now that we have defined honeypots and how they work, we can attempt to
establish their value. As mentioned earlier, unlike mechanisms such as firewalls
and intrusion detection systems, a honeypot does not address a specific problem.
Instead, it is a tool that contributes to your overall security architecture.
The value of honeypots and the problems they help solve depend on how you build,
deploy, and use them.

Honeypots have certain advantages and disadvantages that affect their value.
In this chapter we will examine those advantages and disadvantages more closely.
We will also look at the differences between production and research honeypots
and their respective roles.

Advantages Of Honeypots

Honeypots have several advantages unique to the technology. We will review
four of them here.

Data Value

One of the challenges the security community faces is gaining value from
data. Organizations collect vast amounts of data every day, including firewall
logs, system logs, and Intrusion Detection alerts. The sheer amount of
information can be overwhelming, making it extremely difficult to derive any
value from the data. Honeypots, on the other hand, collect very little data, but
what they do collect is normally of high value. The honeypot concept of no
expected production activity dramatically reduces the noise level. Instead of
logging gigabytes of data every day, most honeypots collect several megabytes of
data per day, if even that much. Any data that is logged is most likely a scan,
probe, or attackinformation of high value.

Honeypots can give you the precise information you need in a quick and
easy-to-understand format. This makes analysis much easier and reaction time
much quicker. For example, the Honeynet Project, a group researching honeypots,
collects on average less then 1MB of data per day. Even though this is a very
small amount of data, it contains primarily malicious activity. This data can
then be used for statistical modeling, trend analysis, detecting attacks, or
even researching attackers. This is similar to a microscope effect. Whatever
data you capture is placed under a microscope for detailed scrutiny.

For example, in Figure 4-1 we see a scan attempt made against a network of
hon-eypots. Since honeypots have no production value, any connection made to a
honeypot is most likely a probe or attack. Also, since such little information
is collected, it is very easy to collate and identify trends that most
organizations would miss. In this figure we see a variety of UDP connections
made from several systems in Germany. At first glance, these connections do not
look related, since different source IP addresses, source ports, and destination
ports are used. However, a closer look reveals that each honeypot was targeted
only once by these different systems. Analysis reveals that an attacker is doing
a covert network sweep.

Figure 4-1 Covert network sweep by an attacker picked up by a network of honeypots

He is attempting to determine what systems are reachable on the Internet by
sending UDP packets to high ports, similar to how traceroute works on Unix. Most
systems have no port listening on these high UDP ports, so when a packet is
sent, the target systems send an ICMP port unreachable error message. These
error messages tell the attacker that the system is up and reachable.

The attacker makes this network sweep difficult to detect because he
randomizes the source port and uses multiple source IP addresses. In reality, he
is most likely using a single computer for the scan but has aliased multiple IP
addresses on the system or is sniffing the network for return packets to the
different systems. Organizations that collect large amounts of data would most
likely miss this sweep, since multiple-source IP addresses and source ports make
it hard to detect. However, because honeypots collect small amounts of, but
high-value data, attacks like these are extremely easy to identify. This
demonstrates one of the most critical advantages of honeypots.

Resources

Another challenge most security mechanisms face is resource limitations, or
even resource exhaustion. Resource exhaustion is when a security resource can no
longer continue to function because its resources are overwhelmed. For example,
a firewall may fail because its connections table is full, it has run out of
resources, or it can no longer monitor connections. This forces the firewall to
block all connections instead of just blocking unauthorized activity. An
Intrusion Detection System may have too much network activity to monitor,
perhaps hundreds of megabytes of data per second. When this happens, the IDS
sensor's buffers become full, and it begins dropping packets. Its resources
have been exhausted, and it can no longer effectively monitor network activity,
potentially missing attacks. Another example is centralized log servers. They
may not be able to collect all the events from remote systems, potentially
dropping and failing to log critical events.

Because they capture and monitor little activity, honeypots typically do not
have problems of resource exhaustion. As a point of contrast, most IDS sensors
have difficulty monitoring networks that have gigabits speed. The speed and
volume of the traffic are simply too great for the sensor to analyze every
packet. As a result, traffic is dropped and potential attacks are missed. A
honeypot deployed on the same network does not share this problem. The honeypot
only captures activities directed at itself, so the system is not overwhelmed by
the traffic. Where the IDS sensor may fail because of resource exhaustion, the
honeypot is not likely to have a problem. A side benefit of the limited resource
requirements of a honeypot is that you do not have to invest a great deal of
money in hardware for a honeypot. Honeypots, in contrast to many security
mechanisms such as firewalls or IDS sensors, do not require the latest
cutting-edge technology, vast amounts of RAM or chip speed, or large disk
drives. You can use leftover computers found in your organization or that old
laptop your boss no longer wants. This means that not only can a honeypot be
deployed on your gigabit network but it can be a relatively cheap computer.

Simplicity

I consider simplicity the biggest single advantage of honeypots. There are no
fancy algorithms to develop, no signature databases to maintain, no rulebases to
misconfigure. You just take the honeypot, drop it somewhere in your
organization, and sit back and wait. While some honeypots, especially research
honey-pots, can be more complex, they all operate on the same simple premise: If
somebody or someone connects to the honeypot, check it out. As experienced
security professionals will tell you, the simpler the concept, the more reliable
it is. With complexity come misconfigurations, breakdowns, and failures.

Return On Investment

When firewalls successfully keep attackers out, they become victims of their
own success. Management may begin to question the return on their investment, as
they perceive there is no longer a threat: "We invested in and deployed a
firewall three years ago, and we were never attacked. Why do we need a firewall
if we have never been hacked?" The reason they were never hacked is the
firewall helped reduce the risk. Investments in other security technologies,
such as strong authentication, encryption, and host-based armoring, face the
same problem. These are expensive investments, costing organizations time,
money, and resources, but they can become victims of their own success.

In contrast, honeypots quickly and repeatedly demonstrate their value.
Whenever they are attacked, people know the bad guys are out there. By capturing
unauthorized activity, honeypots can be used to justify not only their own value
but investments in other security resources as well. When management perceives
there are no threats, honeypots can effectively prove that a great deal of risk
does exist.

For example, once I was in Southeast Asia conducting a security assessment
for a large financial organization. I was asked to do a presentation for the
Board of Directors on the state of their security. As always, I had a honeypot
running on my laptop. About 30 minutes before the presentation, I connected to
their network to make some last-minute changes. Sure enough, while I was
connected to their network, my system was probed and attacked. Fortunately, the
honeypot captured the entire attempt. In this case the attack was a Back Orifice
scan. When the attacker found my system, they thought it was infected and
executed a variety of attacks, including attempting to steal my password and
reboot the system. I then went with this captured attack and used it to open my
presentation to the Board. This attack demonstrated to the Board members that
not only did active threats exist but they tried, and succeeded, in penetrating
their network. It is one thing to talk about such threats, but demonstrating
them, keystroke by keystroke, is far more effective. This proved extremely
valuable in getting the Board's attention.